The present invention relates to an acoustic device and uses thereof. It finds particular application in conjunction with separation of particles or oil droplets, and will be described with particular reference thereto. However, it is to be appreciated that the present exemplary embodiment is also amenable to other like applications.
Large-scale growth of bacteria, yeast, and mammalian cells for numerous industrial and pharmaceutical biotechnology applications use methods for cell separation. Large-scale growth of algae biomass for biodiesel production also requires separation of the cell biomass from the carrying fluid. Inclined gravity settlers have been successfully applied to cell cultures for supporting continuous perfusion culture. Devices using high frequency ultrasonic standing waves to separate particles (e.g. cells) and oil droplets from aqueous solutions have been described in Wang, Z; P. Grabenstetter, D. L. Feke, and J. Belovich. Retention and viability characteristics of mammalian cells in an acoustically driven polymer mesh, Biotechnology Progress, 20, 384-387, 2004; Gaida, T., Dolbhoff-Dier, O., Strutzenberger, K., Burger, W., Groschl, M., Handl, B., and Benes, E., “Selective retention of viable cells in ultrasonic resonance field devices,” Biotechnol Prog., 12, 73-76, 1996; Gupta, S. and Feke, D. L. “Filtration of particulate suspensions in a acoustically driven porous media”, AlChE Journal 44: 1005-1014, 1998; Kilburn, D. G., Clarke, D. J., Coakley, W. T. and Bardsley, D. W., “Enhanced sedimentation of mammalian cells following acoustic aggregation,” Biotechnol. Bioeng., 34(4): 559-562, 1989; Pui, P. W. S., Trampler, F., Sonderhoff, S. A., Groeschl, M., Kilburn, D. G., and Piret, J. M., “Batch and semicontinous aggregation and sedimentation of hybridoma cells by acoustic resonance fields”, Biotechnol. Prog., 11, 146, 1995; Ryll, T., Dutina, G., Reyes, A., Gunson, J., Krummen, L., Etcheverry, T. “Performance of small-scale CHO perfusion cultures using an acoustic cell filtration device for cell retention: characterization of separation efficiency and impact of perfusion on product quality”, Biotechnology and Bioengineering, Vol 69, No. 4, pp. 440-449, 2000; and Trampler, F.; Piret, J. M.; Sonderhoff, S. A.; Kilburn, D. G. Acoustic filter for separating and recycling suspended particles 5626767, 1997.
However, the large scale separation of particles with diameters 1-20 microns from aqueous solution is difficult to accomplish in a cost-effective manner. Advantageously, the present invention provides an improved settling device and uses thereof that overcome these problems.